The present invention relates to a line guide for a fishing rod, and more particularly to a line guide for a fishing rod, provided with a frame having an oblong ring mounting hole and tilted toward the rod tip end, a mounting portion for being mounted onto a rod body, and an oblong guide ring member fitted in the ring mounting hole.
In general, a line guide to be mounted externally on a fishing rod is composed of a hard guide ring member, a frame supporting the guide ring member in an inserted state, a mounting portion for being mounted onto a fishing rod body, and the like. A fishing line fed from a reel is caused to pass through the guide ring member.
There are many demands for this type line guide. Among these, it is most important that the line guide is light in weight as much as possible and it is possible to easily release the line entanglement.
In order to easily release the line entanglement, it is proposed to largely tilt the frame toward the fishing rod tip end. For instance, the line guide shown in FIG. 30 is described in Japanese Utility Model Laid-Open No. 167765/1986. In this line guide a, a frame c having a ring mounting hole 6 is largely tilted toward the fishing rod tip end, and a guide ring member d is fitted in the ring mounting hole b. And, since the frame c is tilted, an aperture diameter of the guide ring member becomes small in the vertical direction, in order to compensate for this, an oblong guide ring member d is used with its longitudinal length extending in the back and forth directions.
In such a line guide a, by applying a tension to the fishing line e even if the fishing line e entangles around the frame c, the entangled portion is caused to pass forwardly (in the right direction of FIG. 30), sliding from a slant surface f of the frame c through the upper surface of the guide ring member d.
In not only the guide ring member d of the above-described line guide a but also other guide ring members, a cross section, intersecting perpendicularly to the circumferential direction of the guide ring member d, of the line guide for a fishing rod is generally shown in FIG. 31. In this case, a cross-section h perpendicular to the circumferential guide ring member g is in the form of a substantially semi-circle at any position. The guide ring member g is inserted into the ring mounting hole k so that a linear outer surface i of the cross section h is in contact with an inner circumferential edge l of the ring mounting hole k. The other surface than the outer surface i of the cross section h is composed of an arcuate surface forming an inner circumferential surface m of the guide ring member g and another arcuate surface through which the inner circumferential surface m and the outer surface i are continuous to each other to make a side end surface n.
The cross section h of the guide ring member g takes such a shape so that, even if the fishing line caused to pass through the hole of the guide ring member g is brought into contact with the inner circumferential surface m at any angle in a rather wide range, a sliding resistance of the fishing line is as small as possible without the fishing line contacting with the edge portion or the curved surfaces defined by a very small radius of curvature.
When the guide ring member takes an oblong shape, there is a problem that a dimension of the guide ring member is increased to rather increase the weight.
Accordingly, it is possible to take such an approach that an entire thickness of the guide ring member is decreased. However, with such an approach, since a radius of curvature r of the side end surface n of the cross section h of the guide ring member becomes very much small, according to an angle of the fishing line passing through the guide ring member, there is raised a problem that the sliding resistance is increased.
Furthermore, if the guide ring member d takes the oblong shape, since the shrinkage amount upon molding is different between the transverse direction and the longitudinal direction, it is very difficult to ensure a necessary dimensional precision for the guide ring member d.
Accordingly, it is possible to take such an approach that the precision of the dimension of the guide ring member d depends upon the polishing work after molding. However, in the case where the guide ring member d has an oblong shape, it is difficult to determine reference position for the polishing work or the like. Accordingly, it is actually very difficult to polish the semi-circular portions at both end portions in the longer axial direction with precision.
For this reason, there are many cases, as shown in FIG. 32, that the dimension of the molded oblong guide ring member d, in particular, the dimension in the longer axial direction is L which is longer than the longitudinal dimension l of the ring mounting hole b of the frame c or is L' which is smaller than that. The dimensions are not identical.
Accordingly, the productivity of the frame c and the guide ring member d in the product line is worse, or even if the guide ring member d is once inserted into the mounting hole b, there is a problem that the guide ring member d is removed or pulled apart in use.
In particular, when a large load is applied to the guide ring member d when fish is caught or the collision shock is caused when the knots or sinkers are abutted against the guide ring member d, there are cases in which, the guide ring member is unexpectedly removed or pulled apart with ease.
As mentioned above, in general, a line guide to be mounted externally on a fishing rod is composed of a hard guide ring member, a frame supporting the guide ring member in an inserted state, a mounting portion for being mounted onto a fishing rod body, and the like.
A line guide a shown in FIG. 33 is shown in Japanese Utility Model Laid-Open No. 35268/1991. In FIG. 33, reference character c denotes a frame which is formed in a ring by punching a metal plate into an annular shape. The frame c is coupled with a mounting pipe p through a support c' that is integral with the frame c. An annular guide ring member d is pressingly inserted into a hole u of the frame c.
There are many demands on the performance for this type line guide. Among these, such factors are important that the frame is light in weight, its mechanical strength is high, the guide ring member is firmly retained and hardly removed, the guide ring member is hardly cracked and it is easy to release the fishing line entanglement.
One of the approaches for easily releasing the fishing line entanglement is that the oblong guide ring member is largely tilted toward the fishing rod tip end.
In the above-described line guide a, the guide ring member d is retained simply by pressingly inserted it into the frame c. In addition, the frame c is simply punched out of the metal plate. In comparison with the thickness of the guide ring member d, the area to be pressingly fitted to the frame c only corresponds to the thickness of the frame c. For this reason, there is a problem that the retainment of the guide ring member d is not always ensured.
For this reason, in general, an adhesive is applied between the frame c and the guide ring member d to thereby maintain a mounting strength of the guide ring member d.
However, even if the adhesive is applied, the effective adhesive area only depends upon the thickness of the frame c. There is no insurance that the guide ring member d will be retained.
Furthermore, in the case where the guide ring member d takes an oblong shape, it is rather difficult to realize the high precision of the dimension of each part. It is therefore unexpectedly difficult to firmly retain the guide ring member d only by the press-fitting it into the frame c.
If the press-fitting between the guide ring member d and the frame c is insufficient, there is a fear that, when the strong shock is applied to the guide ring member d to some extent, the guide ring member d would be pulled apart. In particular, when a fishing line is cast or the fishing line is abruptly wound up while the fish is being caught, in the case where any large knots of the fishing line or any loosened part of the fishing line is collided against the guide ring member d, it is likely that the guide ring member d might easily be released or removed.
Accordingly, there is an approach that a flange is provided on the guide ring member d and the flange is engaged with the opening edge portion of the hole u of the frame c from the front side to thereby prevent the guide ring member d from being pulled apart.
However, with such an approach, it is inevitable that the thickness of the guide ring member d is increased. As a result, the amount of exposure of the guide ring member d is increased. Corresponding to this, there is a problem that it is likely that the guide ring member d would be damaged.
As mentioned above and in conjunction with FIG. 31, in general, the cross section perpendicular to the circumferential direction of the guide ring member g is shown in FIG. 31 so that the fishing line e caused to pass through the hole u of the guide ring member g is out of contact with the corner portions. Namely, the above-described cross section h is substantially in the form of a semi-circle, the linear portion i of the cross section h is in contact with the inner circumferential edge l of the ring mounting hole k, and the corner portions n through which the above-described linear portion i of the cross section h and the reminder portion m are continuous with each other are in the form of arcuate shapes having a radius r of curvature.
The mounting of the guide ring member g onto the frame c is carried out so that its engagement condition may be stable. Also, in order to render the fishing line e to be out of contact with the frame c, to some extent, it is inevitable that the mounting is carried out under the condition that the guide ring member g projects from the frame c. In general, as shown in FIG. 31, the mounting is carried out so that the exactly mid-portion of the linear portion i of the cross section h is in contact with the inner circumferential edge l.
For this reason, also in the above-described line guide a, there is a fear that the part projecting from the frame c of the guide ring member g serves as a wall, and the fishing line e that has slid along and on the frame c is hooked on the wall. In particular, in the case where the upper surface of the frame c or the fishing line e is wet (actually wet in fishing), the fishing line e is kept contacting to the frame c. Accordingly, there is a high possibility that the fishing line would be hooked on or around the guide ring member g.